The Trouble with Science Homework
by theawwesomeeridan
Summary: Tenya is working very hard on his science project. His class is learning about biology and how genes work. The only issue, is that his work has hit a bit of a snag. Asking Tensei about it leads to him finding out more than he thought possible about his brother and Ms. Midnight.


Tenya looked at the data he had just gathered for his science project. It wasn't adding up. They were supposed to be studying how genes are passed on by recording different traits of everyone in their immediate family and showing Punnett Squares correlating to them. The only issue was, his data wasn't making any sense.

The assignment began with blood types. Simple enough. Tenya had A blood, the most common in Japan. That made complete sense.

What didn't was that his parents had claimed B and O types. His father's genotype had to be OO, since O is recessive, and his mother's was either BB or BO. Tensei also had B blood like their mother, meaning his genotype must be BO. Even both of his brother's husbands had B blood. None of that made sense in the context of Tenya having A blood. No matter how he looked at it, the data didn't change.

He looked through his science text book again, hoping that some sort of answer would present itself. Tenya was a smart kid, and yet he could only find one answer to all of this. To find out if he was right, he was going to have to ask Tensei.

Never before had he been so glad that his brother had chosen to live in the Iida complex with his husbands. That made it a much easier quest to find him. He knocked on the front door of their house.

"Tensei-nii? Are you home? I have some questions regarding my science project."

It took a few moments, but the door opened wide, thanks to the button Tensei had had installed after he came home from the hospital.

"Sure, lil dude. What's up?" Tenya was led into the kitchen where Tensei had clearly been trying to cook something or other. His husbands must have both been on hero duties if they had failed to stop him.

Tenya put his notes on the table, checking them again to make sure that they hadn't changed in his walk over here.

"Tensei-nii..." Tenya took a steadying breath, bracing himself for what he was about to ask. "Am I adopted?"

Tensei stopped in his tracks, turning his chair to look back at Tenya. "What brought this up, Ya?"

"It's just that..." Tenya found himself at a loss of words, a very strange sensation for the normally verbose teen. He clenched his left hand, a sort of comforting movement despite how it pulled at his injuries. It was a familiar pull by now. He had some words now. "Do you remember how I was asking about different phenotypes earlier? We're studying genes and their presentations in biology right now. I'm- Tensei-nii, I'm the only one with A type blood and it isn't making any sense."

Tensei did the exact last thing that Tenya was expecting. He started laughing. Full belly laughing that Tenya could only watch for the seeming eternity until he calmed down enough to speak. "I'm sorry... I'm sorry. This is a very serious discussion, but damn. Leave it to you to find the nerdiest way possible to figure it out."

"Figure it out? So, there is something that you've been keeping from me. What is it?"

"You know, most kids would have just fudged some things to make the assignment work and leave it at that."

"That is entirely unethical, and you still haven't answered my question."

"Would it help you at all to know that your mother has A blood, too?"

"A-Are you saying that Father-" Tenya's breath caught in his throat before he could hiss out, "cheated?"

At that, Tensei sobered up, looking at Tenya a bit sadly. "No. Don't think ill of them Tenya, this is entirely my fault. It might not mean much after what I'm about to say, but I love you, Ya. I always have, and I always will." This time it was Tensei who needed a deep breath before he could continue. "Tenya, you're my son."

"Your... Your son?" Tenya blindly groped for a chair behind him, collapsing into it. He swallowed around the new lump in his throat. This was... This was more than he had ever expected. "Who... My mother...?" He looked at Tensei, hoping he understood what he was asking.

"You already know her. We went to school together, actually met up through Shouta. She was in class B while Hizashi and I were in A, so we didn't interact much until Shouta transferred in to the hero course. They were friends from middle school, so when he started eating lunch with us, she joined in." Tensei was looking right at Tenya, and never before had he felt the gaze to be so hard to meet.

"Her name?"

"Kayama Nemuri. The R Rated Hero: Midnight."

"Y-you and-and Midnight-sensei?" Tenya felt so lightheaded that he should be seeing black by now. This was nothing near what he had thought was going to happen when he confronted Tensei.

"She wasn't quite as... risqué when we were younger. We just were stupid kids doing what stupid kids do."

"I don't do anything close to that."

"You're not a stupid kid." Tensei grinned before he looked down at the hands in his lap. "We should have told you. It was unfair of us to keep something this big from you."

"Who... Who all knows?"

"Mother and Father, obviously. Shouta and Hizashi, as well. They were the ones to throw Nemuri the baby shower, after all." At Tenya's raised eyebrow he changed his tune slightly. "Alright, Hizashi threw the baby shower and Shouta was unwillingly dragged along. They were already dating at that point."

"Why did you give me up? Why did you never tell me?"

"It was a really hard decision, but... By the time you were born, we knew we didn't belong together. Friends, yes, but we just didn't work in a romantic relationship. Maybe we just didn't try hard enough, but we both knew that I had a crush on our friends. It wasn't fair to trap her into a relationship that I couldn't commit my all to. We were both fifteen, in the hero course. We barely had time for our own selves, let alone a baby and a relationship. My parents... Mother and Father took care of you while I was at school. They took turns on and off shift just like they had when I was a child. The real deciding factor was when you were almost seven months old. You called my mother 'mama.' It was... decided by everyone that it would be best for you if they raised you as their own. We were kids ourselves, on track for really dangerous careers, and we weren't even together."

"You still never told me."

"The time never seemed right. I didn't... I could never figure out the words to tell you, but I had sworn that if you ever asked, I'd be truthful."

"Th-thank you for that at least." Tenya stood up, clutching the stupid assignment to his chest like a lifeline. "I need to go think about some things."

"Take all the time you need. I'll be here if you have any questions."

Tenya ran from the house, back to his own room, back to his own bed, where he had woken up this morning when the world made sense. When his brother had been his brother and his family was fine. Now everything was flipped on its head, and he had no clue what to do.

He fell into a fitful sleep after staring at the ceiling for what felt like hours. He had school the next day, and he couldn't just skip it. That wouldn't be what a hero does, even if they really wanted to stay under their covers and forget that the world existed. 

Tenya dragged himself to class, even earlier than usual as he had forgone his daily run. He had too much time to think as he stared down at his unfinished science project. It wasn't due for another three weeks, but now it seemed like a monumental task to complete.

So wrapped up in his thoughts, was he, that he hadn't heard the door open. He didn't realize that he was no longer alone until someone sat backwards in the chair in front of his desk and cleared their throat. He jolted in his seat, knocking the papers around on his desk.

"A-Aizawa-sensei? What are you doing here so early?"

"Let's go with Sho-nii right now." At the beginning of the school year, Tenya had put strict boundaries between home and school life. This was Shouta's way of saying this was a personal matter. "Tensei told me what happened last night, kid. How are you holding up?"

"I... Honestly, I don't know. It's a pretty big change. I mostly feel... lied to. Slightly betrayed?" Tenya looked back down at his desk, fixing the papers again.

"If you ever need to talk, Hizashi and I are also here. If anyone can handle the oddities of the Iida household, it's us."

"I guess this makes you my step fathers instead of brothers-in-law, doesn't it?" Another thing that had to change. They're starting to pile up. Tenya felt he might just drown under all of them.

Shouta shrugged. "We're still fine with you calling us nii-san if it makes you feel better. Doesn't really matter to us. You're a good kid, Ya. No matter whose genes you have." He reached across Tenya's desk to ruffle his hair.

"Sho-nii! I have to fix that now!" Tenya gets his emergency comb out of his backpack. "But... I do believe thanks are in order. It really helps to know that you're still the same after everything."

"Course I am. I changed a few of your diapers. Nothing changes after that." Shouta stood up and put his hands in his pockets, shoulders slouching. "I got some shit to get done before the rest of the class gets here. Don't sweat about the science project too much. You still have time."

With that, Tenya was left all alone again. He strangely felt better after their little talk. Perhaps he should have gone to Sho-nii in the first place. He put the science project away, waiting much more calmly for the rest of the early morning. 

His good mood was completely destroyed after lunch. Hero class. Aizawa-sensei had them all change into their hero outfit and meet up at Ground Beta. Fine enough, in and of itself, until Tenya realized who the faculty member on rotation to help them today was. Midnight stood there in her normal attire, and Tenya felt his throat close up again. This could not be happening to him.

Midnight grinned as she watched her students fight. The lesson of the day was Unconventional Thinking Methods. Heroes constrained to one way of solving a problem were nearly useless in most real-world battle situations. Midnight had been working on this assignment for a month now.

It had to be perfectly balanced for each of the unique students and their usual way of dealing with problems. Those that took a more head on approach got puzzles that needed solving. Those who stood back to assess everything before acting would be forced to listen to their guts. These kids had good instincts, they needed to trust them.

The most difficult one by far was Iida's. Perhaps she was a bit biased, but he was clearly the brightest, most level-headed student to come through UA the entire time she had been teaching. In the end, she had decided to give him an obstacle course that he would have to complete without using his engines. With a quirk that requires a specific fuel, being able to go without might one day be a necessity. Some of the others, she had had to bind to make sure they followed her rules, but for Iida, all she had had to do was post a sign that said, "No Engine Emission Allowed."

She watched him specifically for a bit before turning her attention to the rest of the screens showing the other students. She couldn't play favorites, and he was doing so well. Some of the other students were not so much. Midnight was just finishing up a critique for Bakugo about trying to explode another faux villain when Shouta came into the room.

"Ah, look at all their youthful vigor, Shouta! Doesn't it just make you feel all warm and fuzzy on the inside?" She licked her lips slowly, looking at him through the side if her eye. "Or on the outside as the case may be?"

"He knows, Nemuri." Shouta was staring straight ahead at the wall of screens as if he hadn't just dropped a bombshell on her. "Tensei had to tell him last night."

"Right…" Her eyes returned to Iida, watching his wipe some sweat of his brow before continuing. "He's doing quite well."

"Yes, how you and Sei managed to have a child that actually follows rules is beyond me." Shouta dropped into one of the observation chairs.

"Your boy's not doing too bad either." Midnight turned her attention to the screen with Hitoshi on it. His challenge involved using the capture weapon with a time limit. He had to increase his speed and confidence with it.

"Guess I should tell him at some point. Only person in the family who doesn't know, now."

"Well, they are technically brothers by adoption. Might actually help Tenya adjust if someone else is, too."

Shouta stuffed his hands into his pockets, looking for all the world like a hobo riding a train than a teacher observing his class. "I think Hitoshi might take this even worse. He's much more controlled by his emotions than your spawn."

Midnight hummed noncommittally, turning her focus back to the class. Poor Tenya. He really hadn't deserved to be lied to for so long, but it was too late for that. They just had to move forward from here.


End file.
